Wilde (p. 490) expresses the general opinion when he asserts that ‘the use of copper invariably preceded that of bronze.’ He well explains by two reasons why so few antique implements of pure copper have been found in Ireland: either a very short period elapsed between the discovery of treating the pure ores and the introduction of bronze; or the articles, once common, were recast and converted into the more valuable mixed metal. The latter cause is made probable by the early intercourse with Cornwall, one of the great tin emporia. ‘Tin-stone’ (native peroxide of tin or stannic acid) is produced in small quantities by Ireland, and Dr. Charles Smith[237] declares that he collected it. Wilde also notices, in the Royal Irish Academy, weapons, tools, and ornaments of red metal or pure copper. These are thirty celts of the greatest simplicity and the earliest pattern, rudely formed tools, a few fibulæ, a trumpet, two battle-axes, and several Sword-blades of the short, broad, and curved shape usually called scythes. [Illustration: FIG. 77.—COPPER CELTS IN THE DUBLIN COLLECTION.] The pure copper celts, formed upon two or three types, are the oldest in the Dublin collection, and were probably the immediate successors of the stone implement. As a rule they have one side smoother than the other, as if they had been run into simple stone moulds; they are also thicker and of rougher surface than the bronze article. For the most part they are rude and unornamented wedges of cast metal: a few are lunette-shaped and semilunar blades. The cleansed specimens show a great variety of colour. When first found, the brown crust, peculiar to the oxidised metal, readily distinguishes them from the bronze patina, the beautiful varnish of æruginous or verdigris hue, artificial malachite resembling in colour the true native carbonate of copper. [Heading: _COPPER SWORDS._] The broad scythe-shaped Swords, numbering forty-one, are supposed to be ‘specially and peculiarly Irish.’ The straight blades are shown by their large burrs, holes, and rivets either to end in massive handles of metal, or to be attached to wooden staves, long or short. Of this kind some are curved. As many are of ‘red bronze’ (pure copper), darkened by oxidation, it is probable that they are of great antiquity, like the celts of that period. Although in some cases the points have been broken off, yet the edges are neither hacked, indented, nor worn; hence the conclusion that they were true stabbing Swords. Yet Mr. John Evans declares that he knows no such thing as a copper Sword. In this matter he partially follows Lévesque de la Ravalière, who declared copper arms unknown to the Greeks[238] and Romans, Gauls and Franks: this savant was refuted and charged with unfairly treating his authorities by the Comte de Caylus in a description of seven copper Swords dug up (1751) at Gensal in the Bourbonnais. The Abbé Barthélemy attributed seven copper blades to the Franks in the reign of Childeric.